305 engine help?

hi right now am having this problem and it gets me mad well here it goes: i have an 84 chevy with fully built th350 tranny and 305 engine when ever am driving rolling at any speed i floor it and truck responds but truck will pick up speed very slow,also when stalling like at 3,200 and floor it truck will pull like if your not pushing the gas all the way down it will launch super slow and pick up speed slow i think truck is running like a 20 second quarter mile that how slow it feels...well i know my engine is not matching on what it has right now but i think it should pull way more than it is right now...i wanted to know what is causing this to happen thanks...

engine specs: 305 sbc, stock pistons, stock cylinder heads,stock valves, stock crank almost everything stock, no headers, with flowmaster...

except for: 600cfm edelbrock carb, edelbrock performer intake, double roller timing chain, and 280h comp cam...

tranny: th350 with trans go shift kit, blue clutch pack, and everything heavy duty

torque converter: DACCO 3200+ stall

stock gears, one legger differential...

well sorry for all this all i want to know what would be the problem right now that the truck feels heavy when i floor it, what is it that i have wrong right now that is making this...truck is slow what could this be??? thanks jerry


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Too little engine,too much converter.You really need a stock or H.D. Converter due to the weight of the truck to make the torque to get it moving.You also picked a cam that makes peak from 2500-6500 RPM,bad choice! with stock heads and an intake that is rated off idle to 5000 RPM(but it does go rumbity,rump,rump) you killed off all your low end torque, the max with your combo should have been the 268H, actually the 260H would have been better with what you have.

yeah i new it cuz truck wont pull hard and for the cam i just installed it for the sound and the tranny i got it fixed its cuz am upgrading engine to a 355 sbc with L31 vortec heads and a performer rpm vortec intake,flat top pistons 10.3:1 compression ratio with 64cc...and bout the cam comp cams told me i needed a 2,500+ stall and the tranny shop ordered me a 3,200+ stall cuz of the weight of the truck and also for the 280h comp cam...

so with which cam am better off with this 355 sbc using my 3,200 stall???

or should i use the 280h comp cam in the 355sbc with the vortec heads and performer rpm vortec intake with flat top pistons and long tube headers or what cam should be better for this setup guys using my 3,200+ stall???

thanks in advance...

IMO I think even with a 355 and those head you will still be overcamed, exspecley for a heavy truck.

Skeeter

Had a guy that lived in my neighborhood. He used to come hang around while I worked in the shop, got to be where he'd stop by often, always asking questions.

Turns out, he was building a 305 at his house, for a '85 Chevy van.

He did pretty good- had 1.84" heads, Performer/Q-Jet, headers, all fresh. But then he cammed it w/a Competition Cams 268.

The van was (is?) a stone!!! With a stock torque converter and highway gears, this thing was literally dangerous to drive- you did not have enough room on a freeway on-ramp to get up to the speed limit from a dead stop, floored all the way until you had to merge! What a DOG.

At first, I thought it was timing and carb tuning. But it wasn't. He actually had done enough homework to have gotten fairly close in the tune-up.

It was the cam, combined w/the weight and gear ratio (had a TH350).

I would use nothing more than a 260, possibly less in a similar set-up.

The 280 cam can probably be made to work in a Vortec headed 355, but attention needs to be paid to how it's built, obviously- CR, "squench", timing curve, gears, etc.

Good luck!

its cuz i want to run like a 12high to mid 12's in my 84 chevy short bed with this 355 with vortec heads,performer rpm vortec intake, long tube headers, hiperuetectic flat top pistons,600cfm edelbrock carb, double roller timing chain,with fully built tranny with a 3,200 stall and stock gears or maybe 3.73's which are required for my stall and with a trans am posi differential...what cam would be great for my setup to get this tank to run at least a low 13 but 12's would be better any help plz??? i know i need the torque to get this tank moving help plz...which cam???

I'm not good at choosing cams- but I'm willing to bet there's someone who's well versed who will be able to help.

on mine i run a 3200 stall and on a small block it's operating at 2800 .
i put the torquer cam kit in mine .went with the torque shift kit also .
your carb will need to be bigger for the swap , 650 tuned up to 700 guts .
i have huge 35 tires and it launches great .with a quadra junk carb off a 454 .
you can put in gear and walk away .
it will not move till you push the petal .
running a 3:73 gear in mine also .
if that torque converter is junk from factory , you'll feel like your pulling a boat .
i towed a guy home one day , said it was dragging , trans he thought ,but , he put power steering fluid in master cylinder .
that will expand with heat and apply brakes and you want know it is the problem .

well i want is for someone to help me get a great combo for my 355sbc in my 84 chevy to make it run a low 13 to high or mid 12's using vortec heads and my 3,200 stall??? can anyone throw me a good to great combo that will make my 84 chevy pull strong off the line and in mid range and to pull strong when rolling while flooring it and run good...??? what intake and cam???

thanks in advance... jerry

anyone???

how heavy is your car, what gears do you have?how much hp are you looking for?

What will really make a difference is how much money do you have or want to spend. Then someone will be able to help you figure something out. Cole

its an 84 chevy short bed stock weight, and stock gears...but i would like to run 3.73's gears and i already have a fully built tranny with a 3,200+ stall with a 355 sbc i want to run it with a 600cfm edelbrock carb and L31 vortec heads what would be a great combo for my truck to run a low to mid 12's using my 3,200 stall and vortec heads...i know since the truck is heavy i need torque i would like for the truck to haul asz help plz...i would like for the truck to run atleast a low 13 to mid or low 12's i prefer for it to run 12's i would like to have a strong off the line launch with strong mid range torque for my tank to move thanks jerry

IMO i dont think you will reach your goal with ALL stock oem parts, a good pair of heads can free up some good hp and would help.

Just a thought..... why would you build up a 305 and not a 350? should bolt right in and youll get more hp